Auto merge of #9832 - metajack:suppress-reflows, r=mbrubeck

Suppress reflows before RefreshTick or FirstLoad

This fixes a bug where partially loaded content is displayed to the user
before it should be, usually before stylesheets have loaded. This commit
supresses reflows until either FirstLoad or RefreshTick, whichever comes
first.

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1 files changed, 20 insertions, 1 deletions

diff --git a/components/layout/layout_thread.rs b/components/layout/layout_thread.rs
index a361e42fb15..1a8bdfb4a19 100644
--- a/components/layout/layout_thread.rs
+++ b/components/layout/layout_thread.rs
@@ -22,7 +22,7 @@ use euclid::size::Size2D;
 use flow::{self, Flow, ImmutableFlowUtils, MutableFlowUtils, MutableOwnedFlowUtils};
 use flow_ref::{self, FlowRef};
 use fnv::FnvHasher;
-use gfx::display_list::{ClippingRegion, DisplayList, LayerInfo};
+use gfx::display_list::{ClippingRegion, DisplayItemMetadata, DisplayList, LayerInfo};
 use gfx::display_list::{OpaqueNode, StackingContext, StackingContextId, StackingContextType};
 use gfx::font;
 use gfx::font_cache_thread::FontCacheThread;
@@ -114,6 +114,9 @@ pub struct LayoutThreadData {
     /// A queued response for the client {top, left, width, height} of a node in pixels.
     pub client_rect_response: Rect<i32>,
 
+    /// A queued response for the node at a given point
+    pub hit_test_response: (Option<DisplayItemMetadata>, bool),
+
     /// A queued response for the resolved style property of an element.
     pub resolved_style_response: Option<String>,
 
@@ -458,6 +461,7 @@ impl LayoutThread {
                     content_box_response: Rect::zero(),
                     content_boxes_response: Vec::new(),
                     client_rect_response: Rect::zero(),
+                    hit_test_response: (None, false),
                     resolved_style_response: None,
                     offset_parent_response: OffsetParentResponse::empty(),
                     margin_style_response: MarginStyleResponse::empty(),
@@ -977,6 +981,9 @@ impl LayoutThread {
                     ReflowQueryType::ContentBoxesQuery(_) => {
                         rw_data.content_boxes_response = Vec::new();
                     },
+                    ReflowQueryType::HitTestQuery(_, _) => {
+                        rw_data.hit_test_response = (None, false);
+                    },
                     ReflowQueryType::NodeGeometryQuery(_) => {
                         rw_data.client_rect_response = Rect::zero();
                     },
@@ -1119,6 +1126,18 @@ impl LayoutThread {
                     let node = unsafe { ServoLayoutNode::new(&node) };
                     rw_data.content_boxes_response = process_content_boxes_request(node, &mut root_flow);
                 },
+                ReflowQueryType::HitTestQuery(point, update_cursor) => {
+                    let point = Point2D::new(Au::from_f32_px(point.x), Au::from_f32_px(point.y));
+                    let result = match rw_data.display_list {
+                        None => panic!("Tried to hit test with no display list"),
+                        Some(ref dl) => dl.hit_test(point),
+                    };
+                    rw_data.hit_test_response = if result.len() > 0 {
+                        (Some(result[0]), update_cursor)
+                    } else {
+                        (None, update_cursor)
+                    };
+                },
                 ReflowQueryType::NodeGeometryQuery(node) => {
                     let node = unsafe { ServoLayoutNode::new(&node) };
                     rw_data.client_rect_response = process_node_geometry_request(node, &mut root_flow);